Despite being in the minority, the most successful films of 2013 which starred
strong female characters earned film studios the most money

Of the 50 most successful films of 2013, those featuring female characters have brought in bigger American box office revenue than those that didn't.

Entertainment website Vocativ undertook a study of the top 50 biggest box office films in America from the previous year and applied the Bechdel Test to them. The Bechdel Test determines a level of gender equality in a film. To pass, the film must have at least two women in it who talk to each other about something other than a man.

Vocativ found 17 of the 50 films, 36 per cent, passed the test, with a further seven deemed "dubious". The remaining 26, 52 per cent of the total, failed.

However, those 24 contributed to a American box office gross of $4.22 billion, while the 26 that failed generated half that amount: $2.66 billion.

There were blockbuster movies in both categories: Pacific Rim, worth $102 million, and Monsters University, $268 million, both failed the test. So did The Hobbit: The Desolation of Smaug (although it's worth noting that JRR Tolkein's novel had no female characters) and another children's animation, Cloudy with a Chance of Meatballs 2, which brought in $116 million. Star Trek Into Darkness, which earned $229 million, featured two or more female characters but they didn't speak to eachother.

Female buddy cop movie The Heat and superhero film Man of Steel helped contribute to the total of $4.22 billion, earning $160 million and $291 million respectively. The Hunger Grames, which stars Jennifer Lawrence as the teenage warrior Katniss, was the most profitable, bringing in $391 million. There were also a number of animated childrens films which passed, including Despicable Me 2 ($368 million), The Smurfs 2 ($71 million) and Frozen ($248 million).

Sandra Bullock (left) and Melissa McCarthy in The Heat (2013)

Also boosting the total was Gravity, which was listed in the "dubious" category. However its $254 million was added to the pass total, despite it technically failing, as Vocativ ruled: "There are only two main characters onscreen in the movie, and Sandra Bullock is one of them. She’s also onscreen way more than co-star George Clooney. It grossed $254.6 million domestically, so even if we had included it in the fail total, the clear victor would remain the same."

The statistics are encouring after a year when The Bechdel Test, which originated in 1985, again became a conversation point in the film industry after Swedish cinemas introduced a rating depending on if a new film passed or not.